Minigun Infantry - Cost: $100
The Minigunner is the main GDI infantry unit, and is the best all round infantry unit available. They can be built quickly and cheaply, and can inflict a reasonable amount of damage en mass considering their low cost.

Engineer - Cost: $500
Engineers are unarmed infantry units, but offer a wide array of strategic options in battle. One engineer has the potential to cause extreme damage to an enemy building and bring it under your control, they can also repair your own buildings by entering them, and restoring them to full health.
3 Engineers are required to fully capture an enemy structure; 1 to damage it, 2 to bring it under your control and the 3rd to repair it.

Rocketeer - Cost: $300
The GDI Rocketeer carries shoulder mounted rocket launcher that is very effective against vehicles, structures, infantry and aircraft. Because of the increased weight of the rocket launcher, rocket infantry are slower than mingunners but are more heavily armoured.

Grenadier - Cost: $160
The Grenadier throws grenades which are explosive and, in groups are very effective against heavy armour and structures. The time spent throwing the grenade is substantial so that they are usually not able to cause much injury to moving infantry units.

Flame Infantry - Cost: $1000
The commando is the ultimate unit, and is the most versatile GDI infantry unit. His main weapon is ineffective against tanks, but kills enemy infantry units from extreme range. He also has the ability to plant C4 charges on enemy structures which levels them in seconds!

Humm-Vee - Cost: $400
Designed for hit and run tactics, as well as recon, the Humm-Vee sacrifices armour for speed. But it is not completely without merit. The speed means you can run over infantry. It's mounted machine gun means that it can take out infantry, but nothing else.

Medium Tank - Cost: $800
The best all round tank, it has the perfect combination of armour, firepower and speed. It really has the same advantages as the Light Tank, but it's more powerful and can withstand more pounding as it's slower speed stop speedy get-a-ways.

Mobile Rocket Launch System (MRLS) - Cost: $800
This is the longest range weapon GDI posses, using its 277MM missiles it can decimate everything, including airbourne units! However, it doesn't have great armour, ROF and no short-range fighting ability, so you need to keep it behind your front lines in an attack.

APC - Cost: $700
This vehicle is similar to the Humm-Vee except with a little less speed, more armour, and can carry upto 5 troops, it's even armed with the same gun as the Hummer. It is designed for getting a number of troops to and from areas quickly and safely.

Mammoth Tank - Cost: $1500
The sight of the Mammoth Tank strikes fear into even the most battle hardened commando.
It has stupidly huge amounts of armour and firepower. Of course you have to pay for this, and it's in the speed department, so it's always best to have other units around to draw fire and take out pesky infantry whilst you concentrate the main firepower on destroying structures. The slow ROF means it's not so great against infantry, but the mounted rocket launcher ensures that pesky aircraft are kept at bay.

Tiberium Harvester - Cost: $1400
The Harvester is your main source of collecting resources to turn into money to enable you to purchase structures and units to defeat your opponent. It collects Tiberium and brings it back to the Refinery where it is converted into money. When travelling to and from the Tiberium it moves slowly, but it is heavily armoured. They are easy target for enemy commanders so they should always be escorted.

ORCA VTOL Assault Craft - Cost: $1200
As the name suggests, the Orca Fighter can take off and land vertically. It is very fast moving and is armed with TOW rockets to for quickly weakening poorly defended structures or attacks. It can easilly be shot down however, and when it runs out of missiles it must return to base to reload.

Transport Helicopter - Cost: $1500
As the name suggests, the Chinook Transport Helicopter is able to transport 5 infantry units anywhere on the map quickly. It has the added advantage of being able to take engineers or tactical strike teams into the heart of an enemy's base without having to go through ground defences.

Mobile Construction Vehicle (MCV) - Cost: $3000
The MCV is the most important ground unit at the start of any game, as it forms the heart of your base, and allows you to produce structures and defences. If you lose your only MCV in battle, then you can no longer expand your base, and so every building you lose you cannot replace, unless you build another MCV, which are very expensive.

Hovercraft - Cost: $N/A
The Hovercraft is capable of carrying up to 5 infantry or vehicles and transporting them by sea. It has no weapons, but is very fast so can get away from danger. The Hovercraft can only be loaded/un-loaded on shore terrain where it is at its most vunerable.

Gunboat - Cost: $N/A
The mainstay of the GDI naval army. It is equiped with Tomahawk Missiles which can decimate structures quicikly. Also its heavy armour and long range make it ideal for off-shore offencives.